1. Field of the Invention
This invention is related in general to data storage systems. In particular, the invention consists of a system for providing and accessing spare data storage devices.
2. Description of the Prior Art
Computer data storage systems typically include servers, switches, and high-capacity disk arrays for storing digital information. Maintaining the integrity of data stored within the computer data storage system is a major concern. This concern has resulted in the development of numerous methods and techniques for maintaining data integrity during movement and storage within the computer data storage systems.
One important technique is the utilization of dynamic drive sparing (“DDS”), wherein a data storage server can access one or more spare data storage devices to replace a data storage device that has failed or has been taken off line for maintenance. To be effective, this sparing process should not significantly impact data storage system performance or data integrity. However, permanent data loss may occur if the demand for spare data storage devices exceeds the available number of such devices.
In U.S. Pat. No. 6,609,213, Nam Nguyen et al. disclose a system and method for recovering from a server failure in a computer network using several stand-alone, non-clustered serves and a spare server. However, the spare server is used as a backup for the network servers and does not provide backup services in the event an independent storage device fails. Accordingly, it would be desirable to have a server that manages access to spare storage devices.
In U.S. Pat. No. 6,598,174, Ronald Parks et al. disclose a method to detect early disk failure warning and ways to migrate data to other drives in a non-redundant array environment. However, Park's disclosed invention requires equipment for detecting an impending failure and copying data before the original drive fails. It would be advantageous to have a system for providing a spare drive when a drive fails or is removed without warning.